3 Strategies for Maximizing Email Deliverability

Let’s get one thing straight: deliverability is sexy. Don’t let anyone tell you otherwise. It’s the only way your emails get seen, opened, and clicked on. And if you can increase your deliverability by even just 1%, it can have a significant impact on your ROI.

But achieving high deliverability rates that could make even a mailman jealous doesn’t come easy. Think of it this way: as an email marketer, you’re like the friendly neighborhood mailman. Every house that you deliver email to has a guard dog (ISP). And on days when you have junk mail (spam) or aren’t friendly to folks on your route (poor IP reputation), these dogs will chase you away and only let you deliver some of your mail. To maximize your email deliverability, you need to be familiar with these three deliverability tactics:

1. Set Lower Bounce Thresholds

When you hear the word “bounce,” you might think about fun trampolines or bounce houses. But for marketers, when an email bounces, it’s like bouncing on a trampoline except without all the fun with about 100 times the danger. Okay, I might be exaggerating—but there are definitely some business risks involved. To understand why, let’s first define soft bounces and hard bounces.

Soft bounce: A temporary problem with email deliverability that can be due to an unavailable server or full inbox.

Emails that soft bounce over and over again should be retired from future campaigns. If an email continuously soft bounced 10 times in the last 10 campaigns, it might be soft bouncing for reasons other than a temporary server issue. To keep your deliverability rate high and the risk of that soft bounce becoming something more, it’s best to retire that email for good.

Hard bounce: A permanent failure to deliver an email, usually as a result of the email address being non-existent, invalid, or blocked.

The less hard bounces, the better. ISPs prefer senders to have low hard bounce rates because it shows that you take care of your email lists and keep them fresh. Furthermore, because a hard bounced email may be invalid, non-existent, or blocked entirely, it’s a great candidate for a spam trap, which is an inactive, deliverable email address owned by an ISP to catch spammy senders.

Hitting a spam trap will severely hurt your deliverability and sender reputation, especially with a specific ISP, and could potentially put your IP address on a blacklist, an online database of spammy senders. Once your IP is on a blacklist, you’ll find it awfully difficult to get your emails delivered.

So what should you do to improve your soft bounce and hard bounce rates? Employ a bounce management strategy! Here’s how:

Managing soft bounces: Whether you use an email service provider (ESP) or a marketing automation solution, you should be able to set a soft bounce threshold. Oftentimes, these are set to a conservative number like 10 soft bounces = a hard bounce or an email that should be retired from email campaigns for good. To see how we manage soft bounces here at Marketo, check out my previous blog.

Managing hard bounces: Retire all invalid address hard bounces immediately. Most email providers and marketing automation solutions do this for you, but not all do, so make sure that any email that hard bounces is removed from your list. And if you’re using an ESP where you load email lists into the campaign from an external data source like SQL tables or Microsoft Access, be sure to regularly export all of your hard bounces and add them into a suppression list after each campaign. Then, scrub them against your email database when running a list selection.

2. Don’t Buy Lists

Whether you’ve been doing email marketing for a while or you’re a brand new business just starting up, buying an email list and having a larger email database can seem attractive, but it’s generally a poor practice and it may be detrimental to your deliverability rates and sender reputation. Here are four reasons why:

1. Unsolicited emails: If your recipients have never heard from you before or never opted in to receive your communications, your emails could look like spam to them.

When an email recipient marks you as spam, your sender reputation will decrease and ISPs will be suspicious of your activities. With enough spam complaints, you could land your IP on a blacklist, ultimately making it harder for all your future emails to be delivered to the folks who actually opted-in to your communications.

2. Quality: You can’t always trust the quality of a list. You don’t know where the names came from, whether the email addresses are correctly formatted, and whether they’ve been scrubbed for spam traps or syntax errors. The email addresses could be old and the demographics can be all over the place. You just never really know what you’re getting yourself into.

3. Spam Rate: Email service providers and marketing automation solutions typically have spam rate thresholds in place so if you receive a certain percentage of spam complaints per email delivered, they may terminate your contract. This is because if you are using IP addresses associated with an ESP or marketing automation solution and you’re sending spam, it’s a bad reflection on them as well to ISPs. And they need to maintain good standing relationships with ISPs to properly service their other clients. I’ve heard that for some ESPs, if your spam rate goes above 0.5%, they’ll reach out to you to do a full audit of your sending behaviors and list hygiene practices. They don’t want to jeopardize their business reputation just because you had to buy some lists.

4. Bad Metrics: This one should be obvious. Your email metrics will plummet with bad lists! These people didn’t want to hear from you, so very few of them will open and click your emails. Is getting a few email clicks worth losing customer engagement? No, especially when you have to explain the reason to your executives.

3. Segment by Engagement

Getting an ISP to love you is no easy task. Getting all of them to love you is arguably more difficult than getting your celebrity crush to love you. Believe me, I know (you know where to find me, Adele). The number one thing ISPs love to see is high levels of engagement, which means lots of recipients opening, clicking, reading, scrolling, and engaging with your emails on a regular basis.

When you have high email engagement, ISPs will allow the majority of your emails to hit the primary inbox because the demand from your recipients is high. This is called inboxing, which is the percentage of emails that hit the primary inbox as opposed to the spam folder or junk folder. So how do you use email engagement your advantage to get more email inboxing?

Let’s take a look at four scenarios based on this mock situation:

Let’s say you send 100,000 emails that all get delivered. Of those 100,000 emails, 20k engaged within the last 90 days and the remaining 80k haven’t shown any engagement in more than 90 days (the numbers in the examples are made-up based off of my previous experience with campaigns of this nature).

Scenario 1: If you were to just send emails to the engaged group of 20k, the open rate would be 18%, the click-through rate would be 3%, and the unsubscribe rate would be 0%. I’m assuming the unsubscribe rate is 0% because typically when people just engaged, they aren’t likely to unsubscribe. So these are great metrics!

Scenario 2:Conversely, if you only sent an email to the 80k group of unengaged emails, the open rate would be 3%, the click through rate would be 0.2%, and the unsubscribe rate is a little high at 0.31%. Metrics that could definitely be better. Again, these numbers are just to illustrate a point.

Scenario 3:Now, if you send an email to all 100,000 at the same time, the open rate would be a 6% open rate, with a 0.76% CTR, and a 0.25% unsubscribe rate. This example is probably what most marketers do and therefore the metrics you’d expect based on this example.

Scenario 4:If you take a different approach and only send the email to the group of 20k engaged email addresses first, wait 30 minutes, and then send the email to the group of 80k unengaged emails, you’ll get better inboxing rates. This is because when you send emails to engaged recipients first, the ISPs will boost your reputation based on the high engagement on that email. So, when you send to the group of unengaged emails, you’ll actually get higher inbox placement just because you warmed up your sender reputation. In this example (and similar experiences I’ve had), by sending the 20k engaged emails first, inboxing for the group of 80k unengaged emails increased from 55% to 70% when email sends were staggered. The overall effect on inboxing was an increase from 63% to 75%, which definitely moves the needle!

Key takeaway: If you stagger your sends by engagement, you’ll see higher deliverability rates and much higher inboxing. This is a really cool strategy that not too many people use today, but it is extremely effective.

Deliver results

Get your emails delivered and placed in the primary inbox by following the three deliverability strategies I’ve outlined. First, set lower soft bounce and hard bounce thresholds to reduce your risk of hitting spam traps and hurting your sender reputation. Second, do not, I repeat, do not purchase lists. You can’t always control for list quality or cleanliness. Lastly, stagger your email sends by levels of engagement. You’ll achieve better inboxing and overall stronger email metrics.

Do you have any deliverability tips or tricks that work for you? Share them in the comments below! And, for more deliverability tips and a deeper dive into deliverability strategies, join me for my upcoming webinar “7 Plays to Make Your Email Deliverability Unstoppable” on February 18th. Register here!

We will handle your contact details in line with our
Privacy Policy. If you prefer not to receive marketing emails
from Marketo, you can opt-out of all marketing communications or customize your preferences
here.